1. Field of the Invention
The present invention relates generally to fiber optic electronic components, and more particularly is a fiber optic transceiver package.
2. Description of the Prior Art
Computers and related peripheral equipment, and satellite and communication systems, have in the recent past evolved extremely rapidly. These systems require ever increasing data transfer rates to perform the highly complex tasks that drive the systems, such as digital signal processing, image analysis, and communications. With current demands, optical couplers are used to transfer signals over short and long distances between computers, between two circuit boards in one computer, and even between multiple chips on a single printed circuit board. The use of high speed optical signals in place of electrical interconnections increases the achievable data transfer rate.
An optical transmitter/receiver module typically includes both light emitting devices such as vertical cavity surface emitting lasers (VCSEL's) and light detecting devices such as photodiodes. Driver/receiver circuitry modules, typically in the form of application specific integrated circuit (ASIC) chips, include driver circuitry which receives electrical signals from one device and drives the VCSEL's in response. The ASIC also includes receiver circuitry for receiving signals from the photodiodes and, in response, for processing those signals into an appropriate output. The combination of the VCSEL's, the photodiodes, and the ASIC circuitry is commonly referred to as an optical transceiver or a fiber optic transceiver.
To provide heat dissipation means and EMI (electro-magnetic interference) protection for the circuitry of the transceivers, the transceivers are enclosed in packages. The main subject of this invention is the XFP (10 gigabit small form factor pluggable module) package that includes, per MSA (Multi Source Agreement) standards, a set of EMI dissipation fingers. The subject fingers are referred to as the intermediate rear EMI gasket in XFP MSA 2003, drawing FIG. 40. The gasket presents an additional component that must be assembled when constructing the package. In addition to the time and expense represented by this assembly process, the junction of the gasket with the main body of the transceiver cage represents an area of potential mechanical failure.
Accordingly, it is a main object of the present invention to provide an improved package for an optic transceiver that integrates the intermediate rear EMI gasket into the main body of the fiber optic transceiver package.